U.S. Pat. No. 3,300,540 issued Jan. 24, 1967, discloses a process for the preparation of allenes comprising the reaction of a 3-halo-1-alkyne with a triorgano aluminum compound. The organo substituent in the aluminum compound is disclosed to be any group that does not deactivate the reagents, preferably hydrocarbon such as alkyl, cycloalkyl, aryl, aralkyl and cycloalky-alkyl. There is no disclosure nor suggestion that the organo substituent groups in the aluminum compound could bear fluorine atoms.
R. N. Haszeldine et al., Journal of the Chemical Society, 2040 (1954) disclose the preparation of 4,4,4-trifluorobuta-1,2-diene (alternate name 1-(perfluoromethyl)-1,2-propadiene) by the reaction of 4,4,4-trifluoro-2-iodobut-1-ene with ethanolic potassium hydroxide. There is no disclosure nor suggestion that this synthesis route would be applicable for the synthesis of higher members of the perfluoroalkyl substituted allene series.
An oral presentation by D. J. Burton entitled "Advances in the Chemistry of Fluorine-Containing Organometallic Reagents" at the American Chemical Society Ninth Winter Fluorine Conference, Jan. 29-Feb. 3, 1989, St., Petersburg, Fla., addressed the preparation, structure and synthetic utility of fluorine-containing organocadmium, organozinc and organocopper reagents.
P. L. Coe and N. E. Milner, Journal of Organometallic Chemistry, 70, 147(1974) disclosed the reaction of perfluoro-n-heptyl copper with propargyl bromide at 110.degree. C. to be an extremely violent exothermic reaction that afforded, after a difficult workup that included a minor explosion, a 10% yield of 1-(perfluoro-n-heptyl)-1,2-propadiene. There is no disclosure nor suggestion relating to a means of performing said conversion in a safe, controllable, reproducible, high-yield manner.
Thus, there is a need for a suitable safe general synthetic route for the preparation of perfluoroalkyl substituted allenes, as well as for other intermediates useful in the production of fluorocarbon polymers.
It is therefore an object of the present invention to provide a controllable high yield process for the preparation of perfluoro substituted allenes.
It is a further object of the present invention to provide novel bis-allenyl substituted perfluoroalkane compounds.
It is a further object of the present invention to provide a process for the preparation of these novel diallenic compounds.